Data processing device and data processing method

ABSTRACT

The present technology relates to a data processing apparatus and a data processing method that can reduce errors of time arising from accuracy of time information. 
     The data processing apparatus generates signaling including time information having accuracy of time according to a frame length of a physical layer frame and processes the signaling so as to be included into a preamble of the physical layer frame to make it possible to reduce errors of time arising from time information. The present technology can be applied, for example, to a transmitter compatible with a broadcasting method of ATSC3.0 and so forth.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/765,861, filed Apr. 4, 2018, the entire contents of which areincorporated herein by reference. U.S. application Ser. No. 15/765,861is a National Stage of PCT/JP2016/083466, filed Nov. 11, 2016, andclaims the benefit of priority from Japanese Application No.2015-229768, filed Nov. 25, 2015.

TECHNICAL FIELD

The present technology relates to a data processing apparatus and a dataprocessing method, and particularly to a data processing apparatus and adata processing method that can reduce errors of time arising fromaccuracy of time information.

BACKGROUND ART

As one of broadcasting methods for the next generation, formulation ofATSC (Advanced Television Systems Committee) 3.0 is being advanced (forexample, refer to NPL 1). In ATSC3.0, it is supposed to provide anadvanced service by introducing, as a transmission method, not anMPEG2-TS (Transport Stream) method widely spread at present but an IP(Internet Protocol) transmission method in which an IP packet that isused in the field of communication is used for digital broadcasting.

CITATION LIST Non Patent Literature [NPL 1]

ATSC Candidates Standard: Physical Layer Protocol (Doc. S32-230r21 28Sep. 2015)

SUMMARY Technical Problem

Incidentally, in data transmission by a broadcasting method such asATSC3.0, an error in time sometimes arises from accuracy of timeinformation included in signaling transmitted by a physical layer frame,and a proposal for reduction of errors of time arising from accuracy oftime information is demanded.

The present technology has been made in view of such a situation asdescribed above, and it is an object of the present technology to reduceerrors of time arising from accuracy of time information.

Solution to Problem

The data processing apparatus according to a first aspect of the presenttechnology is a data processing apparatus including a generation sectionconfigured to generate signaling including time information havingaccuracy of time according to a frame length of a physical layer frame,and a processing section configured to process the signaling so as to beincluded into a preamble of the physical layer frame.

The data processing apparatus according to the first aspect of thepresent technology may be an independent apparatus or may be an internalblock that configures one apparatus. Further, the data processing methodof the first aspect of the present technology is a data processingmethod corresponding to the data processing apparatus of the firstaspect of the present technology described above.

In the data processing apparatus and the data processing method of thefirst aspect of the present technology, signaling including timeinformation having accuracy of time according to a frame length of aphysical layer frame is generated, and the signaling is processed so asto be included into a preamble of the physical layer frame.

The data processing apparatus according to a second aspect of thepresent technology is a data processing apparatus including a processingsection configured to process signaling included in a preamble of aphysical layer frame and including time information having accuracy oftime according to a frame length of the physical layer frame.

The data processing apparatus according to the second aspect of thepresent technology may be an independent apparatus or may be an internalblock that configures one apparatus. Further, the data processing methodof the second aspect of the present technology is a data processingmethod corresponding to the data processing apparatus of the secondaspect of the present technology described above.

In the data processing apparatus and the data processing method of thesecond aspect of the present technology, signaling included in apreamble of a physical layer frame and including time information havingaccuracy of time according to a frame length of the physical layer frameis processed.

Advantageous Effect of Invention

With the first aspect and the second aspect of the present technology,errors of time arising from accuracy of time information can be reduced.

It is to be noted that the effect described here is not necessarilyrestrictive and the effect may be any one of the effects described inthe present disclosure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view depicting an example of a configuration of atransmission system to which the present technology is applied.

FIG. 2 is a view depicting a structure of a physical layer frame.

FIG. 3 is a view depicting a result of a simulation of frame time of thephysical layer frame.

FIG. 4 is a view depicting a result of a simulation of frame time of thephysical layer frame.

FIG. 5 is a view illustrating L1 basic information and L1 detailedinformation

FIG. 6 is a view depicting an example of syntax of the L1 basicinformation.

FIG. 7 is a view depicting an example of syntax of the L1 detailedinformation.

FIG. 8 is a view depicting another example of syntax of the L1 detailedinformation.

FIG. 9 is a view depicting comparison in accuracy with an MPEG2-TSmethod.

FIG. 10 is a view depicting an example of syntax of the L1 basicinformation of an L1B+L1D transmission method.

FIG. 11 is a view depicting an example of syntax of the L1 detailedinformation of an L1B+L1D transmission method.

FIG. 12 is a view depicting an example of syntax of the L1 basicinformation of an L1B transmission method a.

FIG. 13 is a view depicting an example of syntax of the L1 detailedinformation of the L1B transmission method a.

FIG. 14 is a view depicting an example of syntax of the L1 basicinformation of an L1B transmission method b.

FIG. 15 is a view depicting an example of syntax of the L1 detailedinformation of the L1B transmission method b.

FIG. 16 is a view depicting an example of syntax of the L1 basicinformation of an L1D transmission method.

FIG. 17 is a view depicting an example of syntax of the L1 detailedinformation of the L1D transmission method.

FIG. 18 is a view depicting an example of a configuration of atransmission apparatus on the transmission side and a receptionapparatus on the reception side.

FIG. 19 is a view depicting an example of a configuration of a waveformprocessing section on the transmission side.

FIG. 20 is a flow chart illustrating a flow of a data process on thetransmission side.

FIG. 21 is a view depicting an example of a configuration of a waveformprocessing section on the reception side.

FIG. 22 is a flow chart illustrating a flow of a data process on thereception side.

FIG. 23 is a view depicting an example of a configuration of a computer.

DESCRIPTION OF EMBODIMENT

In the following, an embodiment of the present technology is describedwith reference to the drawings. It is to be noted that description isgiven in the following order.

-   1. Configuration of System-   2. Overview of Frame Mode-   3. Transmission Method of Time Information-   (1) L1B+L1D transmission method-   (2a) L1B transmission method a-   (2b) L1B transmission method b-   (3) L1D transmission method-   4. Detailed Configuration of Transmission Side and Reception Side-   5. Modifications-   6. Configuration of Computer-   <1. Configuration of System>

(Configuration Example of Transmission System)

FIG. 1 is a view depicting a configuration of an embodiment of atransmission system to which the present technology is applied. It is tobe noted that the term system is a logical set of a plurality ofapparatus.

Referring to FIG. 1, the transmission system 1 includes a transmissionapparatus 10 and a reception apparatus 20. In this transmission system1, data transmission in compliance with a broadcasting method of ATSC3.0(standard for digital broadcasting) or the like is performed.

The transmission apparatus 10 is a transmitter compatible with abroadcasting method of ATSC3.0 or the like and transmits content througha transmission line 30. For example, the transmission apparatus 10transmits a broadcasting stream, which includes (components of) videos,audios and so forth configuring a content of a broadcasting program orthe like and signaling, as a broadcasting wave through the transmissionline 30.

The reception apparatus 20 is a receiver compatible with a broadcastingmethod of ATSC3.0 or the like and receives and outputs contenttransmitted from the transmission apparatus 10 through the transmissionline 30. For example, the reception apparatus 20 receives a broadcastingwave from the transmission apparatus 10 and processes (components of)videos, audios and so forth configuring content and signaling, which areincluded in a broadcasting stream, to reproduce the videos and audios ofthe content of a broadcasting program or the like.

It is to be noted that, in the transmission system 1, the transmissionline 30 may be a terrestrial wave (terrestrial broadcasting) or may besatellite broadcasting that utilizes, for example, a broadcastingsatellite (BS: Broadcasting Satellite) or a communication satellite (CS:Communications Satellite) or cable broadcasting (CATV) that uses acable.

-   <2. Overview of Frame Mode>

(Physical Layer Frame)

FIG. 2 is a view depicting a structure of a physical layer frame used indata transmission in compliance with a broadcasting method of ATSC3.0and so forth.

Referring to FIG. 2, the physical layer frame includes a bootstrap(Bootstrap), a preamble (Preamble) and a payload (Payload). The physicallayer frame is configured with a predetermined frame length such as aunit of millisecond. According to the physical layer frame, after thebootstrap and the preamble are acquired, the succeeding payload can beacquired.

It is to be noted that the bootstrap corresponds, for example, to the P1symbol that configures a T2 frame of DVB-T2 (Digital VideoBroadcasting-Second Generation Terrestrial), and the preamblecorresponds, for example, to the P2 symbol that configures a T2 frame ofDVB-T2. Accordingly, also it can be considered that the bootstrap is thepreamble.

Incidentally, in ATSC3.0, a time-aligned mode (time-aligned mode) and asymbol-aligned mode (symbol-aligned mode) are prescribed as frame modesaccording to the frame length of the physical layer frame.

The time-aligned mode is a mode in which a surplus sample is insertedinto a guard interval (GI: Guard Interval) part to adjust the framelength (frame time) of the physical layer frame to units of integermilliseconds, whereafter the physical layer frame is transmitted.

For example, in the case where broadcasting (for example, datatransmission in compliance with ATSC3.0) and communication (for example,data transmission in compliance with LTE (Long Term Evolution)) are tobe caused to coexist in the same RF channel, if the frame length (frametime) of the physical layer frame is units of integer milliseconds, thenthis is convenient because delimiters of time coincide. However, in thetime-aligned mode, since a surplus sample (meaningless data) istransmitted, data transmission is less efficient.

In the symbol-aligned mode is a mode in which data is transmitted as itis without a surplus sample inserted therein. Since, in thesymbol-aligned mode, a surplus sample is not transmitted, efficient datatransmission can be performed. For example, in DVB-T (Digital VideoBroadcasting-Terrestrial), DVB-T2 and ISDB-T (Integrated ServicesDigital Broadcasting-Terrestrial), data transfer similar to that in thesymbol-aligned mode is performed.

However, in the symbol-aligned mode, since a sample for causingdelimiters of time to coincide with each other is not inserted, inphysical layer frames, not only physical layer frames whose frame length(frame time) is units of integer milliseconds (physical layer framesthat exist along boundaries of milliseconds) but also physical layerframes whose frame length (frame time) is not units of integermilliseconds (physical layer frames that do not exist along boundariesof milliseconds) exist.

Here, a result of a simulation of frame time of a physical layer framein the case where the symbol-aligned mode is set is described withreference to FIGS. 3 and 4.

FIG. 3 indicates a result of a simulation of frame time of a physicallayer frame when, in the case where the FFT mode is an 8K mode and theguard interval (GI) is 1,024, the number of OFDM symbols included in onephysical layer frame is changed. It is to be noted that, in FIG. 3, itis represented by shade whether the frame time is units of integermilliseconds.

Referring to FIG. 3, if attention is paid to a case in which, forexample, the OFDM symbol number is 10, namely, the number of OFDMsymbols included in one physical layer frame is 10, then since thesymbol time of the OFDM and the GI is 1.33 milliseconds, the total OFDMtime is 13.33 milliseconds (=1.33 milliseconds×10). Further, in thisexample, since the time of the bootstrap is 2.00 milliseconds, the framelength is 15.33 milliseconds (=13.33 milliseconds+2.00 milliseconds).

In this case in which the OFDM symbol number is 10, the frame time ofthe first physical layer frame is 15.333 milliseconds, and the frametime of the second physical layer frame is 30.667 milliseconds. Further,the frame time of the third physical layer frame is 46.000 milliseconds(30.667 milliseconds+15.33 milliseconds), and the frame time of thefourth physical layer frame is 61.333 milliseconds (46.000milliseconds+15.33 milliseconds).

Similarly, also in the fifth and succeeding physical layer frames, timewhen 15.33 milliseconds is added to the frame time of a physical layerframe immediately preceding in time can be determined as frame time ofthe physical layer frame of the target. In particular, as the frame timeof the fifth to 25th physical layer frames, 76.667 milliseconds, 92.000milliseconds, 107.333 milliseconds, 122.667 milliseconds, 138.000milliseconds, 153.333 milliseconds, 168.667 milliseconds, 184.000milliseconds, 199.333 milliseconds, 214.667 milliseconds, 230.000milliseconds, 245.333 milliseconds, 260.667 milliseconds, 276.000milliseconds, 291.333 milliseconds, 306.667 milliseconds, 322.000milliseconds, 337.333 milliseconds, 352.667 milliseconds, 368.000milliseconds and 383.333 milliseconds are determined.

In this manner, in the case where the OFDM symbol number is 10, althoughthe frame time of the physical layer frame is units of integermilliseconds at fixed intervals like 46.000 milliseconds, 92.000milliseconds, 138.000 milliseconds, 184.000 milliseconds, 230.000milliseconds, 276.000 milliseconds, 322.000 milliseconds and 368.000milliseconds, also frame time that is not units of integer millisecondsexists.

On the other hand, if attention is paid to a case in which, in FIG. 3,for example, the OFDM symbol number is 12, namely, the number of OFDMsymbols included in one physical layer frame is 12, then since thesymbol time of the OFDM and the GI is 1.33 milliseconds, the total OFDMtime is 16.00 milliseconds. Further, since the time of the bootstrap is2.00 milliseconds, the frame length is 18.00 milliseconds (=16.00milliseconds+2.00 milliseconds).

In the case where the OFDM symbol number is 12, the frame time of thefirst physical layer frame is 18.000 milliseconds, and the frame time ofthe second physical layer frame is 36.000 milliseconds (18.00milliseconds+18.00 milliseconds). Further, the frame time of the thirdphysical layer frame is 54.000 milliseconds (36.000 milliseconds+18.00milliseconds), and the frame time of the fourth physical layer frame is72.000 milliseconds (54.000 milliseconds+18.00 milliseconds).

Similarly, also in the fifth and succeeding physical layer frames, timewhen 18.00 milliseconds is added to the frame time of a physical layerframe immediately preceding in time can be determined as frame time ofthe physical layer frame of the target. In particular, as the frame timeof the fifth to 25th physical layer frames, 90.000 milliseconds, 108.000milliseconds, 126.000 milliseconds, 144.000 milliseconds, 162.000milliseconds, 180.000 milliseconds, 198.000 milliseconds, 216.000milliseconds, 234.000 milliseconds, 252.000 milliseconds, 270.000milliseconds, 288.000 milliseconds, 306.000 milliseconds, 324.000milliseconds, 342.000 milliseconds, 360.000 milliseconds, 378.000milliseconds, 396.000 milliseconds, 414.000 milliseconds, 432.000milliseconds and 450.000 milliseconds are determined.

In this manner, in the case where the OFDM symbol number is 12, theframe time of all physical layer frames is units of integer millisecondslike 18.000 milliseconds, 36.000 milliseconds, . . . , 432.000milliseconds and 450.000 milliseconds.

In particular, in the simulation result of FIG. 3, in the case where theOFDM symbol number is 10, 11, 13, 14, 16, 17, 19 and 20, although theframe time of a physical layer frame becomes units of integermilliseconds at every other two, any other frame time does not becomeunits of integer milliseconds. On the other hand, in the case where theOFDM symbol number is 12, 15, 18 and 21, the frame time of all physicallayer frames is units of integer milliseconds.

Meanwhile, FIG. 4 depicts a simulation result of the frame time of thephysical layer frame when the number of OFDM symbols included in onephysical layer frame is changed in the case where the FFT mode is the 8Kmode and besides the guard interval (GI) is 768. It is to be noted that,also in FIG. 4, it is represented by shade whether the frame time isunits of integer milliseconds.

In the simulation result of FIG. 4, in the case where the OFDM symbolnumber is 15, 21, 24 and 30, although the frame time of the physicallayer frame becomes units of integer milliseconds at every eight, theframe time of any other frame does not become units of integermilliseconds. Further, in the case where the OFDM symbol number is 16,17, 19, 20, 22, 23, 25, 26, 28 and 29, the frame time of all physicallayer frames does no become units of integer milliseconds. On the otherhand, in the case where the OFDM symbol number is 27, the frame time ofall physical layer frames is units of integer milliseconds.

As described above, since, in the symbol-aligned mode, a sample formaking delimiters of time coincide with each other is not inserted,whether or not the frame time of a physical layer frame becomes units ofinteger milliseconds is determined depending upon a combination of theFFT mode or the OFDM symbol number, the guard interval (GI), the symboltime and so forth. For example, while, in the simulation result of FIG.3, the frame time is units of integer milliseconds at a certain ratio,in the simulation result of FIG. 4, the ratio at which the frame time isunits of integer milliseconds is low.

Therefore, in current ATSC3.0, upon data transmission in thetime-aligned mode, since the frame length is an integer multiple of amillisecond, it is supposed that time information transmission bysignaling is transmitted in accuracy of milliseconds. Meanwhile, even inthe case where the symbol-aligned mode is set, although no problemoccurs in a physical layer frame whose frame time is units of integermilliseconds because no error occurs from time indicated by timeinformation, in a physical layer frame whose frame time is not units ofinteger milliseconds, an error (jitters) from time indicated by timeinformation occurs.

Therefore, in the present circumstances, in the case where thesymbol-aligned mode is set, since a physical layer frame with which noerror occurs and a physical layer frame with which an error occursexist, only a physical layer frame with which an error does not occurcan include time information in the signaling. That time information istransmitted only by a specific physical layer frame with which an errordoes not occur in this manner is not preferable to a broadcaster becauseit narrows the degree of freedom in operation or mounting. On the otherhand, in the case where time information is transmitted by a physicallayer frame other than a specific physical layer frame with which anerror does not occur, an error (rounding error) occurs, which is notdesirable to perform processing.

According to the present technology, in order to solve such a problem asdescribed above, the accuracy of time information to be transmitted bythe signaling is made higher than the accuracy of milliseconds in thepresent circumstances such that, even in the case where thesymbol-aligned mode is set as the frame mode, an error does not occur(an error can be reduced) between the time indicated by the timeinformation and the frame time in all physical layer frames.

It is to be noted that the time information transmitted by the signalingrepresents absolute time of a predetermined position in a stream of aphysical layer frame. The time of a predetermined position in a streamis time of a predetermined timing while a bit at a predeterminedposition is being processed by the transmission apparatus 10. Here, thepredetermined position in a stream of a physical layer frame in whichthe time information represents time is referred to as time position.

As the time position, for example, the top position of a physical layerframe that has a preamble in which time information is included(position of the top of the bootstrap) can be adopted. Further, as thetime position, for example, a position of the boundary between thebootstrap and the preamble of a physical layer frame that has thepreamble in which time information is included (the last position of thebootstrap or the top position of the preamble) can be adopted.

Further, as the time position, for example, the last position of thepreamble of a physical layer frame that has the preamble in which timeinformation is included can be adopted. It is to be noted that, as thetime position, an arbitrary position of a physical layer frame can beadopted further.

-   <3. Transmission Method of Time Information>

(Overview of L1 Basic Information and L1 Detailed Information)

FIG. 5 is a view illustrating an overview of L1 basic information and L1detailed information.

Referring to FIG. 5, as the signaling included in the preamble(Preamble) of a physical layer frame, L1 basic information (L1-Basic)and L1 detailed information (L1-Detail) are available.

Here, if the L1 basic information and the L1 detailed information arecompared with each other, then while the L1 basic information isconfigured from a number of bits approximately equal to 200 bits, the L1detailed information is different in size in that it includes 400 toseveral thousands of bits. Further, as indicated by arrow marks in FIG.5, in the preamble, the L1 basic information and the L1 detailedinformation are read out in this order, and therefore, the L1 basicinformation is read out earlier than the L1 detailed information.Furthermore, the L1 basic information is different when compared withthe L1 detailed information also in that it is transmitted morerobustly.

(L1 Basic Information)

FIG. 6 is a view depicting an example of the syntax of the L1 basicinformation (L1-Basic) of FIG. 5. It is to be noted that detailedcontents of the L1 basic information are described in “Table 9.2L1-Basic signaling fields and syntax” of NPL 1 specified hereinabove.

L1b_content_tag of 2 bits represents a tag value for identifying thecontent. L1B_version of 3 bits represents the version of the L1 basicinformation. L1B_slt_flag of 1 bit represents whether or not thereexists an SLT (Service Labeling Table).

L1B_time_info_flag of 1 bit represents whether or not there exists timeinformation. L1B_papr of 2 bits represents application of PAPR (Peak toAverage Power Reduction).

L1B_frame_length_mode of 1 bit represents a frame mode. In the casewhere L1B_frame_length_mode=0, the frame mode is a time-aligned mode. Onthe other hand, in the case where L1B_frame_length_mode=1, the framemode is a symbol-aligned mode.

L1B_frame_length of 10 bits represents a frame length of the physicallayer frame. However, this L1B_frame_length is used only in the casewhere the frame mode is the time-aligned mode, but is not used in thecase where the frame mode is the symbol-aligned mode.

L1B_num_subframes of 8 bits represents a number of sub frames includedin the physical layer frame. L1B_preamble_num_symbols of 3 bitsrepresents a number of OFDM symbols included in the preamble. L1_preamble_reduced_carriers of 3 bits represents a number of control unitsaccording to reduction of the maximum number of carriers of the FFT sizeused in the preamble.

L1B_L1_Detail_size_bits of 16 bits represents a size of the L1 detailedinformation (L1-Detail). L1B_L1_Detail_fec_type of 3 bits represents anFEC type of the L1 detailed information.L1B_L1_Detail_additional_parity_mode of 2 bits represents an additionalparity mode of the L1 detailed information. L1_L1_Detail_total_cells of19 bits represents a total size of the L1 detailed information.

L1B_First_Sub_mimo of 1 bit represents a use situation of MIMO (MultipleInput and Multiple Output) of the top sub frame. L1B_First_Sub_miso of 1bit represents a use situation of MISO (Multiple Input and SingleOutput) of the top sub frame.

L1B_First_Sub_fft_size of 2 bits represents an FFT size of the top subframe. L1_First_Sub_reduced_carriers of 3 bits represents a number ofcontrol units according to reduction of the maximum number of carriersof the FFT size used in the top sub frame. L1B_First_Sub_guard_intervalof 4 bits presents a guard interval length of the top sub frame.

L1B_First_Sub_excess_samples of 13 bits represents a number of surplussamples inserted in the guard interval part in the top sub frame.However, this L1_First_Sub_excess_samples is used only in the case wherethe frame mode is the time-aligned mode, but is not used in the casewhere the frame mode is the symbol-aligned mode.

L1B_First_Sub_num_ofdm_samples of 11 bits represents a number of OFDMsymbols included in the top sub frame.L1_First_Sub_scattered_pilot_pattern of 5 bits presents an SP pattern(Scattered Pilot Pattern) used in the top sub frame.L1B_First_Sub_scattered_pilot_boost of 3 bits represents a value bywhich the magnitude of the SP pattern is increased.

L1B_First_Sub_sbs_first of 1 bit represents the top of an SBS (SubframeBoundary Symbol) of the top sub frame. L1B_First_Sub_sbs_last of 1 bitrepresents the tail end of the SBS of the top sub frame.

L1B_Reserved is a reserved region (Reserved). Although the bit number ofL1B_Reserved is not determined (TSD: To Be determined), in the presentcircumstances, it is 49 bits. L1B_crc of 32 bits represents that a CRC(Cyclic Redundancy Check) value is included.

It is to be noted that, in the case where uimsbf (unsigned integer mostsignificant bit first) is designated as the format (Format), thissignifies that bit arithmetic operation is performed and a result istreated as an integer. On the other hand, in the case where bslbf (bitstring, left bit first) is designated, then a result is treated as a bitstring.

(L1 Detailed Information)

FIG. 7 is a view depicting an example of the syntax of the L1 detailedinformation (L1-Detail) of FIG. 5. However, in the syntax of FIG. 7, aportion that specifically relates to the present technology from withinthe L1 detailed information is described with excerpts. It is to benoted that detailed contents of the L1 detailed information aredescribed in “Table 9.12 L1-Detail signaling fields and syntax” of NPL 1specified hereinabove.

L1D_version of 4 bits represents a version of the L1 detailedinformation.

In a loop according to L1D_num_rf of 3 bits, a parameter relating tochannel bonding (Channel Bonding) is placed. In particular,L1D_rf_frequency of 19 bits represents a frequency of an RF channelcoupled by the channel bonding.

Here, in the case where L1B_time_info_flag=1 in the L1 basic informationof FIG. 7, since this indicates that time information exists,L1D_time_info as time information is placed in the L1 detailedinformation. It is to be noted that the bit number of L1D_time_info isundetermined (TBD).

However, since it is supposed in ATSC3.0 in the present circumstancesthat time information to be transmitted by signaling is transmitted withaccuracy of milliseconds as described hereinabove, it is supposed that,as L1D_time_info, L1D_time_sec of 32 bits and L1D_time_msec of 10 bitsare placed as depicted in FIG. 8. It is to be noted that L1D_time_secrepresents time information in a unit of second. Meanwhile,L1D_time_msec represents time information in a unit of millisecond.

In contrast, in the present technology, as time information of higheraccuracy than the accuracy of a unit of millisecond in the presentcircumstances, time information in a unit of microsecond (usec) and aunit of nanosecond (nsec) is transmitted in addition to time informationin a unit of second (sec) and a unit of millisecond (msec).

It is to be noted that, although a field compatible with the accuracy ofseconds or less can transmit not only time information in a unit ofmillisecond, for example, of 10 bits but time information in a unit ofmicrosecond of 10 bits or time information in a unit of microsecond anda unit of nanosecond of 20 bits, since to transmit, in the case where aservice by broadcasting is performed in the transmission system 1 ofFIG. 1, time information of higher accuracy than necessary by thebroadcasting has such an influence as to compress the transmission band,this is not effective.

Therefore, for example, if it is supposed to utilize the PTP (PrecisionTime Protocol) prescribed in IEEE 1588-2008 as the time information,then since it is possible for the PTP to include a second field and ananosecond field and be ready for the accuracy of a unit of nanosecond,it is assumed that time information of accuracy higher than the accuracyof nanosecond, namely, such time information as exceeds 30 bits, is nottransmitted in addition to time information in a unit of second and aunit of microsecond. However, time information in a unit of microsecondof 10 bits, time information in a unit of microsecond and a unit ofnanosecond of 20 bits or the like is an example, and some other bitaccuracy may be adopted.

Further, although, in the conventional MPEG2-TS method, accuracy of aclock is prescribed by a standard (for example, 27 MHz, 30 ppm), if theerror (rounding error) between time indicated by time information ofsignaling and frame time in the case where the frame mode is thesymbol-aligned mode is compared with the accuracy of the MPEG2-TSmethod, then a result is such as depicted in FIG. 9. In particular, fromthe table of FIG. 9, it is apparent that, although the accuracy of thetime information in a unit of millisecond degrades from the accuracy ofthe MPEG2-TS method, the accuracy of the time information in a unit ofmicrosecond and a unit of nanosecond is improved significantly from theaccuracy of the MPEG2-TS method.

Accordingly, also depending upon the comparison on accuracy with theMPEG2-TS method, it is demonstrated that it is effective to transmittime information in a unit of microsecond of 10 bits or time informationin a unit of microsecond and a unit of nanosecond of 20 bits bysignaling. However, as regards the error (rounding error) of FIG. 9, noerror occurs in the case where the frame mode is the time-aligned modeas described hereinabove, and besides, also in the case where the framemode is the symbol-aligned mode, no error occurs in physical layerframes in which the frame time is a unit of integer millisecond.

Further, in the present technology, the time information described aboveis placed into the L1 basic information and the L1 detailed informationas signaling. Further, only it is necessary for the time information tobe included in at least one of the L1 basic information and the L1detailed information. In the following, four transmission methodsincluding an L1B+L1D transmission method that transmits time informationwith both the L1 basic information and the L1 detailed information, anL1B transmission method 1 and an L1B transmission method b that transmittime information only with the L1 basic information, and an L1Dtransmission method that transmits time information only with the L1detailed information.

(1) L1B+L1D Transmission Method

First, the L1B+L1D transmission method is described with reference tothe syntaxes of FIGS. 10 and 11.

(Syntax of L1 Basic Information)

FIG. 10 is a view depicting an example of the syntax of the L1 basicinformation of the L1B+L1D transmission method. However, in the syntaxof FIG. 10, only characteristic portions are described with excerpts.

In the L1 basic information of FIG. 10, in the case where the frame modeis the time-aligned mode (L1B_frame_length_mode=0), L1B_frame_length of10 bits is placed, but in the case where the frame mode is thesymbol-aligned mode (L1B_frame_length_mode=1), L1B_time_usec of 10 bitsis placed.

Further, in the L1 basic information of FIG. 10, in the case where theframe mode is the time-aligned mode (L1B_frame_length_mode=0),L1B_First_Sub_excess_samples of 13 bits is placed, but in the case wherethe frame mode is the symbol-aligned mode (L1B_frame_length_mode=1),L1B_time_nsec of 10 bits is placed. However, in the case whereL1B_time_nsec of 10 bits is placed, the succeeding 3 bits are used as areserved region (Reserved).

In this manner, in the L1 basic information of the L1B+L1D transmissionmethod, in the case where the frame mode is the symbol-aligned mode,time information in a unit of microsecond (L1B_time_usec) and timeinformation in a unit of nanosecond (L1B_time_nsec) are included.

(Syntax of L1 Detailed Information)

FIG. 11 is a view depicting an example of the syntax of the L1 detailedinformation of the L1B+L1D transmission method. However, in the syntaxof FIG. 11, only characteristic portions are described with excerpts.

In the L1 detailed information of FIG. 11, in the case where timeinformation exists (L1B_time_info_flag=1), L1D_time_sec of 32 bits andL1D_time_msec of 10 bits are placed.

In this manner, in the L1 detailed information of the L1B+L1Dtransmission method, in the case where time information exists, timeinformation in a unit of second (L1D_time_sec) and time information in aunit of millisecond (L1D_time_msec) are included.

In this manner, in the case where the L1B+L1D transmission method isadopted, time information in a unit of second (L1D_time_sec), timeinformation in a unit of millisecond (L1D_time_msec), time informationin a unit of microsecond (L1B_time_usec) and time information in a unitof nanosecond (L1B_time_nsec) are transmitted by the L1 basicinformation and the L1 detailed information. Further, since timeobtained from the time information has accuracy of a unit of nanosecond,in the case where the frame mode is the symbol-aligned mode, the error(jitters) from the time indicated by the time information can besuppressed even with the physical layer frame in which the frame length(frame time) is not units of integer milliseconds.

Further, since the L1B+L1D transmission method can be implemented onlyby utilizing the structure of the L1 detailed information in the presentcircumstances as it is and applying some modification to the structureof the L1 basic information in the current circumstances(L1B_frame_length and L1B_First_Sub_excess_samples that are not used inthe symbol-aligned mode are utilized), the cost for modification can bereduced. Further, since the L1B+L1D transmission method uses manystructures of the L1 basic information and the L1 detailed informationin the present circumstances, it is efficient as well.

It is to be noted that, while the L1 basic information of FIG. 10indicates an example in which time information in a unit of microsecond(L1B_time_usec) and time information in a unit of nanosecond(L1B_time_nsec) are included in the case of the symbol-aligned mode,only time information in a unit of microsecond (L1B_time_usec) mayotherwise be included. Also in this case, time information of accuracyhigher than that of a unit of millisecond is transmitted.

(2a) L1B Transmission Method A

Now, the L1B transmission method a is described with reference to thesyntaxes of FIGS. 12 and 13

(Syntax of L1 Basic Information)

FIG. 12 is a view depicting an example of the syntax of the L1 basicinformation of the L1B transmission method a. It is to be noted that, inthe syntax of FIG. 12, only characteristic portions are described withexcerpts.

In the L1 basic information of FIG. 12, in the case where timeinformation exists (L1B_time_info_flag=1), L1_B_time_sec of 32 bits andL1B_time_msec of 10 bits are placed.

Further, in the L1 basic information of FIG. 12, in the case where theframe mode is the time-aligned mode (L1B_frame_length_mode=0),L1B_frame_length of 10 bits is placed, but in the case where the framemode is the symbol-aligned mode (L1B_frame_length_mode=1), L1B_time_usecof 10 bits is placed.

Furthermore, in the L1 basic information of FIG. 12, in the case wherethe frame mode is the time-aligned mode (L1B_frame_length_mode=0),L1B_First_Sub_excess_samples of 13 bits is placed, but in the case wherethe frame mode is the symbol-aligned mode (L1B_frame_length_mode=1),L1B_time_nsec of 10 bits and Reserved of 3 bits are placed.

It is to be noted that, while L1B_Reserved has 7 bits or 49 bits, thissignifies that, in the case where time information exists, a reservedregion (Reserved) of 7 bits is secured, but in the case where timeinformation does not exist, a reserved region (Reserved) of 49 bits issecured.

In this manner, in the L1 basic information of the L1B transmissionmethod a, in the case where time information exists and besides theframe mode is the symbol-aligned mode, time information in a unit ofsecond (L1B_time_sec), time information in a unit of millisecond(L1B_time_msec), time information in a unit of microsecond(L1B_time_usec) and time information in a unit of nanosecond(L1B_time_nsec) are included.

(Syntax of L1 Detailed Information)

FIG. 13 is a view depicting an example of the syntax of the L1 detailedinformation of the L1B transmission method a. However, in the syntax ofFIG. 13, only characteristic portions are described with excerpts.

In the L1 detailed information of FIG. 13, since time information isplaced on the L1 basic information side, time information(L1D_time_info) is not placed.

As described above, in the case where the L1B transmission method a isadopted, time information in a unit of second (L1B_time_sec), timeinformation in a unit of millisecond (L1B_time_msec), time informationin a unit of microsecond (L1B_time_usec) and time information in a unitof nanosecond (L1B_time_nsec) are transmitted only by the L1 basicinformation. Further, since the time obtained from the time informationhas accuracy of a unit of nanosecond, in the case where the frame modeis the symbol-aligned mode, the error (jitters) from the time indicatedby the time information can be suppressed even with the physical layerframe in which the frame length (frame time) is not units of integermilliseconds.

Further, in the L1B transmission method a, since time information istransmitted only by the L1 basic information that is robust, all timeinformation can be protected sufficiently. Further, in the L1Btransmission method a, since all time information is transmitted by theL1 basic information, it is possible to transmit all time informationcollectively together with the L1 basic information side. Consequently,for example, the reception apparatus 20 can decode the time informationincluded in the L1 basic information more rapidly.

It is to be noted that, while the L1 basic information of FIG. 12depicts an example in which time information in a unit of microsecond(L1B_time_usec) and time information in a unit of nanosecond(L1B_time_nsec) are included in the case of the symbol-aligned mode,only time information in a unit of microsecond (L1B_time_usec) mayotherwise be included. Also in this case, time information of accuracyhigher than a unit of millisecond is transmitted.

(2b) L1B Transmission Method B

Now, the L1B transmission method b is described with reference to thesyntaxes of FIGS. 14 and 15.

(Syntax of L1 Basic Information)

FIG. 14 is a view depicting an example of the syntax of the L1 basicinformation of the L1B transmission method b. However, in the syntax ofFIG. 14, only characteristic portions are described with excerpts.

In the L1 basic information of FIG. 14, L1B_time_info_flag of 1 bit isdeleted while L1B_time_sec of 32 bits and L1B_time_msec of 10 bits arealways placed.

Further, in the L1 basic information of FIG. 14, in the case where theframe mode is the time-aligned mode (L1B_frame_length_mode=0),L1B_frame_length of 10 bits is placed, but in the case where the framemode is the symbol-aligned mode (L1B_frame_length_mode=1), L1B_time_usecof 10 bits is placed.

Furthermore, in the L1 basic information of FIG. 14, in the case wherethe frame mode is the time-aligned mode (L1B_frame_length_mode=0),L1B_First_Sub_excess_samples of 13 bits is placed, but in the case wherethe frame mode is the symbol-aligned mode (L1B_frame_length_mode=1),L1B_time_nsec of 10 bits and Reserved of 3 bits are placed.

In this manner, in the L1 basic information of the L1B transmissionmethod b, in the case where the frame mode is the time-aligned mode,time information in a unit of second (L1B_time_sec) and time informationin a unit of millisecond (L1B_time_msec) are included, and in the casewhere the frame mode is the symbol-aligned mode, time information in aunit of microsecond (L1B_time_usec) and time information in a unit ofnanosecond (L1B_time_nsec) are included in addition to time informationin a unit of microsecond (L1B_time_usec).

(Syntax of L1 Detailed Information)

FIG. 15 is a view depicting an example of the syntax of the L1 detailedinformation of the L1B transmission method b. However, in the syntax ofFIG. 15, only characteristic portions are described with excerpts.

In the L1 detailed information of FIG. 15, since time information isplaced on the L1 basic information side, time information(L1D_time_info) is not placed there at all.

As described above, in the case where the L1B transmission method b isadopted, time information in a unit of second (L1B_time_sec), timeinformation in a unit of millisecond (L1B_time_msec), time informationin a unit of microsecond (L1B_time_usec) and time information in a unitof nanosecond (L1B_time_nsec) are transmitted only by the L1 basicinformation. Further, since the time obtained from the time informationhas accuracy of a unit of nanosecond, in the case where the frame modeis the symbol-aligned mode, the error (jitters) from the time indicatedby the time information can be suppressed even with a physical layerframe in which the frame length (frame time) is not units of integermilliseconds.

Further, in the L1B transmission method b, since time information istransmitted only by the L1 basic information that is robust, all timeinformation can be protected sufficiently. Further, in the L1Btransmission method b, since all time information is transmitted by theL1 basic information, it is possible to transmit all time informationcollectively together with the L1 basic information side. Consequently,for example, the reception apparatus 20 can decode the time informationincluded in the L1 basic information more rapidly. Furthermore,according to the L1B transmission method b, time information can alwaysbe transmitted irrespective of the frame mode such as the time-alignedmode or the symbol-aligned mode.

It is to be noted that, while, in the L1 basic information of FIG. 14,an example is depicted in which time information in a unit ofmicrosecond (L1B_time_usec) and time information in a unit of nanosecond(L1B_time_nsec) are included in the case of the symbol-aligned mode,only time information in a unit of microsecond (L1B_time_usec) mayotherwise be included. Also in this case, time information of accuracyhigher than a unit of millisecond is transmitted.

(3) L1D Transmission Method

Finally, the L1D transmission method is described with reference to thesyntaxes of FIGS. 16 and 17.

(Syntax of L1 Basic Information)

FIG. 16 is a view depicting an example of the syntax of the L1 basicinformation of the L1D transmission method. However, in the syntax ofFIG. 16, only characteristic portions are described with excerpts.

In the L1 basic information of FIG. 16, for L1B_time_info_flag, not 1bit but 2 bits are secured. For example, it is assumed that, in the casewhere L1B_time_info_flag=01, time information in a unit of second and aunit of millisecond is placed. For example, in the case whereL1B_time_info_flag=10, it is assumed that time information in a unit ofmicrosecond is placed in addition to time information in a unit ofsecond and a unit of millisecond. Further, for example, in the casewhere L1B_time_info_flag=11, time information in a unit of microsecondand a unit of nanosecond is placed in addition to time information in aunit of second and a unit of millisecond.

It is to be noted that, in the L1 basic information of FIG. 16, sincetime information is placed on the L1 detailed information side, timeinformation is not placed there at all. Further, in the L1 basicinformation of FIG. 16, since L1B_time_info_flag has 2 bits,L1B_Reserved has 48 bits.

(Syntax of L1 Detailed Information)

FIG. 17 is a view depicting an example of the syntax of the L1 detailedinformation of the L1D transmission method. However, in the syntax ofFIG. 17, only characteristic portions are described with excerpts.

In the L1 detailed information of FIG. 17, in the case whereL1B_time_info_flag=01, time information in a unit of second(L1D_time_sec) and time information in a unit of millisecond(L1D_time_msec) are placed.

On the other hand, in the L1 detailed information of FIG. 17, in thecase where L1B_time_info_flag=10, time information in a unit ofmicrosecond (L1D_time_usec) is placed in addition to time information ina unit of second (L1D_time_sec) and time information in a unit ofmillisecond (L1D_time_msec).

Further, in the L1 detailed information of FIG. 17, in the case whereL1B_time_info_flag=11, time information in a unit of microsecond(L1D_time_usec) and time information in a unit of nanosecond(L1D_time_nsec) are placed in addition to time information in a unit ofsecond (L1D_time_sec) and time information in a unit of millisecond(L1D_time_msec).

In this manner, in the L1 detailed information of the L1D transmissionmethod, time information in a unit of microsecond (L1D_time_usec) ortime information in a unit of microsecond (L1D_time_usec) and timeinformation in a unit of nanosecond (L1D_time_nsec) are included inaddition to time information in a unit of second (L1D_time_sec) and timeinformation in a unit of millisecond (L1D_time_msec) in response to thevalue of L1B_time_info_flag.

In this manner, in the case where the L1D transmission method isadopted, time information in a unit of second (L1D_time_sec), timeinformation in a unit of millisecond (L1D_time_msec), time informationin a unit of microsecond (L1D_time_usec) or time information in a unitof microsecond (L1D_time_usec) and time information in a unit ofnanosecond (L1D_time_nsec) are transmitted only by the L1 detailedinformation. Further, since time obtained from the time information hasaccuracy of a unit of microsecond or a unit of nanosecond, in the casewhere the frame mode is the symbol-aligned mode, the error (jitters)from the time indicated by the time information can be suppressed evenwith a physical layer frame in which the frame length (frame time) isnot units of integer milliseconds.

Further, in the L1D transmission method, since time information istransmitted only by the L1 detailed information, all time informationcan be protected with the same level. Further, in the L1D transmissionmethod, since all time information is transmitted by the L1 detailedinformation, it is possible to transmit all time informationcollectively together with the L1 detailed information side. Therefore,for example, the reception apparatus 20 can easily analyze timeinformation included in the L1 detailed information (time informationconfigured simple).

It is to be noted that, while the L1 detailed information of FIG. 17depicts an example in which three types of time information are placedin response to the value L1B_time_info_flag, only time information in aunit of second (L1D_time_sec), time information in a unit of millisecond(L1D_time_msec) and time information in a unit of microsecond(L1D_time_usec) may otherwise be placed. Also in this case, timeinformation of accuracy higher than a unit of millisecond istransmitted.

Although the four transmission methods including the L1B+L1Dtransmission method, L1B transmission method a, L1B transmission methodb and L1D transmission method are described above, particularly, forexample, such time information as described subsequently is transmitted.In particular, since time information is represented by a binary codeddecimal number (BCD: Binary Coded Decimal), for example, in the L1B+L1Dtransmission method, time information in a unit of millisecond(L1D_time_msec), time information in a unit of microsecond(L1B_time_usec) and time information in a unit of nanosecond(L1B_time_nsec) can be represented as “0.123456789ns.”

In this case, the time information in a unit of millisecond(L1D_time_msec) corresponds to “123” (=0x07c:00_0111_1011b); the timeinformation in a unit of microsecond (L1B_time_usec) corresponds to“456” (=0x1c8:01_1100_1000b); and the time information in a unit ofnanosecond (L1B_time_nsec) corresponds to “789” (=0x315:11_0001_0101b).In particular, in addition to transmission of the time information in aunit of millisecond (L1D_time_msec) that is “123,” also the timeinformation in a unit of microsecond (L1B_time_usec) of “456” and thetime information in a unit of nanosecond (L1B_time_nsec) of “789” aretransmitted as occasion demands. In other words, from within“0.123456789nx” described above, the portion of “456789ns” is the timeinformation of the difference.

It is to be noted that the foregoing description is directed to a casein which, in the case where the frame mode is the symbol-aligned mode,on the assumption that a physical layer frame in which the frame length(frame time) is not units of integer milliseconds (physical layer framehaving accuracy higher than a unit of millisecond) is transmitted, timeinformation of accuracy higher than a unit of millisecond is transmittedas signaling (L1 basic information, L1 detailed information). Here, evenin the case where not only a physical layer frame whose frame length hasaccuracy higher than a unit of integer milliseconds but also a physicallayer frame whose frame length has accuracy of a unit of integermilliseconds is transmitted, time information of accuracy higher than aunit of millisecond may be transmitted as signaling.

In particular, in the case where the timing at which a physical layerframe is sent (started) is not in a unit of millisecond (in the casewhere the timing has accuracy higher than a unit of millisecond) and aphysical layer frame whose frame length is units of integer millisecondsis transmitted, a physical layer frame whose frame time is not units ofinteger milliseconds. Therefore, in this case, by transmitting timeinformation of accuracy higher than a unit of millisecond, it ispossible to suppress the error (jitters) between the time indicated bythe time information and the frame time.

Consequently, even in the case where the frame length of a physicallayer frame is a unit of integer millisecond and besides the timing atwhich the physical layer frame is sent is not in a unit of millisecond,the physical layer frame can be transmitted freely, and therefore, it ispossible to make mounting easier.

-   <4. Detailed Configuration of Transmission Apparatus and Reception    Apparatus>

(Configuration Example of Transmission Apparatus and ReceptionApparatus)

FIG. 18 is a view depicting an example of a configuration of thetransmission apparatus 10 on the transmission side and the receptionapparatus 20 on the reception side.

Referring to FIG. 18, the transmission apparatus 10 includes an inputformat processing section (Input Format) 101, a BICM (Bit InterleavedCoding and Modulation) processing section 102, a frame interleaveprocessing section (Frame and Interleave) 103, and a waveform processingsection (Waveform) 104.

The input format processing section 101 performs a necessary process foran input stream inputted thereto and performs a process for distributinga packet in which data obtained by the process is placed to a PLP(Physical Layer Pipe). The data processed by the input format processingsection 101 is outputted to the BICM processing section 102.

The BICM processing section 102 performs an error correction process andsuch processes as bit interleave and orthogonal transform for the datainputted from the input format processing section 101. The dataprocessed by the BICM processing section 102 is outputted to the frameinterleave processing section 103.

The frame interleave processing section 103 performs such processes asinterleave in a time direction or a frequency direction for the datainputted from the BICM processing section 102. The data processed by theframe interleave processing section 103 is outputted to the waveformprocessing section 104.

The waveform processing section 104 generates an OFDM (OrthogonalFrequency Division Multiplexing) signal on the basis of the datainputted from the frame interleave processing section 103 and transmitsthe OFDM signal through the transmission line 30. It is to be noted thata detailed configuration of the waveform processing section 104 ishereinafter described with reference to FIG. 19.

Meanwhile, in FIG. 18, the reception apparatus 20 includes a waveformprocessing section (Waveform) 201, a frame deinterleave processingsection (Frame and De-Interleave) 202, a De-BICM processing section 203and an output format processing section (Output Format) 204.

The waveform processing section 201 receives an OFDM signal transmittedfrom the transmission apparatus 10 through the transmission line 30 andperforms a signal process for the OFDM signal. The data processed by thewaveform processing section 201 is outputted to the frame deinterleaveprocessing section 202. It is to be noted that a detailed configurationof the waveform processing section 201 is hereinafter described withreference to FIG. 21.

The frame deinterleave processing section 202 performs such a process asdeinterleave in a frequency direction or a time direction for the datainputted from the waveform processing section 201. The data processed bythe frame deinterleave processing section 202 is outputted to theDe-BICM processing section 203.

The De-BICM processing section 203 performs such processes as orthogonaldemodulation, bit deinterleave or an error correction process for thedata inputted from the frame deinterleave processing section 202. Thedata processed by the De-BICM processing section 203 is outputted to theoutput format processing section 204.

The output format processing section 204 performs a necessary processfor the data inputted from the De-BICM processing section 203 andoutputs an output stream obtained by the process.

(Configuration Example of Waveform Processing Section of TransmissionSide)

FIG. 19 is a view depicting an example of a configuration of thewaveform processing section 104 of the transmission apparatus 10 of FIG.18.

Referring to FIG. 19, the waveform processing section 104 includes adata processing section (Data) 131, a preamble processing section(Preamble) 132 and a bootstrap processing section (Bootstrap) 133.

The data processing section 131 performs a process relating to dataincluded in the payload (Payload) of a physical layer frame.

The preamble processing section 132 performs a process relating tosignaling included in the preamble (Preamble) of a physical layer frame.This signaling includes L1 basic information (L1-Basic) and L1 detailedinformation (L1-Detail).

Here, in the case where the L1B+L1D transmission method is adopted, thepreamble processing section 132 generates L1 basic information (FIG. 10)including time information in a unit of microsecond and a unit ofnanosecond (L1B_time_usec, L1B_time_nsec) and L1 detailed information(FIG. 11) including time information in a unit of second and a unit ofmillisecond (L1D_time_sec, L1D_time_msec) and places the generatedinformation as signaling into a physical layer frame.

On the other hand, in the case where the L1B transmission method a orthe L1B transmission method b is adopted, the preamble processingsection 132 generates L1 basic information (FIG. 12 or 14) includingtime information in a unit of second, a unit of millisecond, a unit ofmicrosecond and a unit of nanosecond (L1B_time_sec, L1B_time_msec,L1B_time_usec, L1B_time_nsec) and places the generated information assignaling into a physical layer frame. In this case, the L1 detailedinformation (FIG. 13 or 15) does not include time information.

Further, in the case where the L1D transmission method is adopted, thepreamble processing section 132 generates L1 detailed information (FIG.17) including time information in a unit of second, a unit ofmillisecond, a unit of microsecond and a unit of nanosecond(L1D_time_sec, L1D_time_msec, L1D_time_usec, L1D_time_nsec) and placesthe generated information as signaling into a physical layer frame.However, in this case, the L1 basic information (FIG. 16) does notinclude time information.

The bootstrap processing section 133 performs a process relating to dataor signaling included in the bootstrap (bootstrap) of a physical layerframe.

It is to be noted that, though not depicted in FIG. 19, in the waveformprocessing section 104, a processing section is provided which performsa process for inserting a symbol of a pilot (PILOTS), a process relatingto MISO, a process relating to IFFT (Inverse Fast Fourier Transform), aprocess relating to PAPR and a process relating to the guard interval,and those processes are performed.

(Transmission Side Data Process)

Now, a flow of a transmission side data process executed by thetransmission apparatus 10 of FIG. 18 is described with reference to aflow chart of FIG. 20.

At step S101, the input format processing section 101 performs an inputdata process. In the input data process, a necessary process isperformed for the inputted input stream, and a packet in which dataobtained by the process is placed is distributed to one or a pluralityof PLPs.

At step S102, the BICM processing section 102 performs an encoding andmodulation process. In this encoding and modulation process, an errorcorrection process, such processes as bit interleave or orthogonalmodulation and so forth are performed.

At step S103, the frame interleave processing section 103 performs aframe interleave process. In this frame interleave processes, such aprocess as interleave in a time direction or a frequency direction isperformed.

At step S104, the waveform processing section 104 performs a waveformprocess. In this waveform process, an OFDM signal is generated andtransmitted through the transmission line 30. Further, data or signalingis processed by the data processing section 131, preamble processingsection 132 and bootstrap processing section 133.

Here, in the case where the L1B+L1D transmission method is adopted, thepreamble processing section 132 generates L1 basic information (FIG. 10)including time information in a unit of microsecond and information in aunit of nanosecond (L1B_time_usec, L1B_time_nsec) and L1 detailedinformation (FIG. 11) including time information in a unit of second anda unit of millisecond (L1D_time_sec, L1D_time_msec) and places thegenerated information into the preamble of a physical layer frame.

On the other hand, in the case where the L1B transmission method a orthe L1B transmission method b is adopted, the preamble processingsection 132 generates L1 basic information (FIG. 12 or 14) includingtime information in a unit of second, a unit of millisecond, a unit ofmicrosecond and a unit of nanosecond (L1B_time_sec, L1B_time_msec,L1B_time_usec, L1B_time_nsec) and places the generated information intothe preamble of a physical layer frame.

Further, in the case where the L1D transmission method is adopted, thepreamble processing section 132 generates L1 detailed information (FIG.17) including time information in a unit of second, a unit ofmillisecond, a unit of microsecond and a unit of nanosecond(L1D_time_sec, L1D_time_msec, L1D_time_usec, L1D_time_nsec) and placesthe generated information into the preamble of a physical layer frame.

A flow of the transmission side data process has been described. In thistransmission side data process, by adopting the L1B+L1D transmissionmethod, the L1B transmission method a, the L1B transmission method b, orthe L1D transmission method, signaling is generated in which timeinformation in a unit of second, time information in a unit ofmillisecond, time information in a unit of microsecond and timeinformation in a unit of nanosecond are included in information of atleast one of the L1 basic information and the L1 detailed information,and the signaling is placed into the preamble of a physical layer frame.

Then, since the time obtained from the time information has accuracyhigher than the accuracy of a unit of millisecond (accuracy of a unit ofmicrosecond or accuracy of a unit of nanosecond), in the case where theframe mode is the symbol-aligned mode, when the frame mode is thesymbol-aligned mode, the error (jitters) from the time indicated by thetime information can be suppressed even with a physical layer frame inwhich the frame length (frame time) is not units of integermilliseconds.

Therefore, errors of time arising from the accuracy of time informationtransmitted by signaling can be reduced. Furthermore, it is possible toplace and transmit time information into and together with signalingwithout consciousness of whether or not the frame length of the physicallayer frame (frame time) is units of integer milliseconds (for example,without consciousness of a frame number of a physical layer frame or thelike).

Further, if time information of a unit of microsecond of 10 bits andtime information of a unit of nanosecond of 10 bits are added to thesignaling, then accuracy of a level similar to that of the PTP can beimplemented. Alternatively, if only time information of a unit ofmicrosecond of 10 bits is added, then accuracy that is equal to orhigher than that of a system in the present circumstances and issufficient can be implemented. It is to be noted that, in the lattercase, since time information of a unit of microsecond of 10 bits istransmitted additionally, information for 10 bits is reduced incomparison with that in an alternative case in which both timeinformation of the former is transmitted additionally, and thetransmission efficiency can be improved.

Further, since sufficient accuracy of signaling can be implemented onlyby adding time information of a unit of microsecond or a unit ofnanosecond, as the transmission side data process, there is no necessityto perform a complicated process in comparison with existing processes(it is easy to treat data). Further, since the information to be addedto the signaling is time information itself, it does not have adependence relation with any other parameter included in the signaling,and, for example, even if expansion of standards is performed in thefuture, there is little possibility that the information may beinfluenced by the expansion of standards.

(Configuration Example of Waveform Processing Section of Reception Side)

FIG. 21 is a view depicting a configuration example of the waveformprocessing section 201 of the reception apparatus 20 of FIG. 18.

Referring to FIG. 21, the waveform processing section 201 includes abootstrap processing section (Bootstrap) 231, a preamble processingsection (Preamble) 232 and a data processing section (Data) 233.

The bootstrap processing section 231 performs a process relating to dataor signaling included in the bootstrap (Bootstrap) of a physical layerframe.

The preamble processing section 232 performs a process relating to thesignaling included in the preamble (Preamble) of the physical layerframe. This signaling includes L1 basic information (L1-Basic) and L1detailed information (L1-Detail).

Here, in the case where the L1B+L1D transmission method is adopted,since L1 basic information (FIG. 10) including time information of aunit of microsecond and a unit of nanosecond (L1B_time_usec,L1B_time_nsec) and L1 detailed information (FIG. 11) including timeinformation of a unit of second and a unit of millisecond (L1D_time_sec,L1D_time_msec) are included as the signaling in the preamble of thephysical layer frame, the preamble processing section 232 process thetime information of them.

On the other hand, in the case where the L1B transmission method a orthe L1B transmission method b is adopted, since L1 basic information(FIG. 12 or 14) including time information of a unit of second, a unitof millisecond, a unit of microsecond and a unit of nanosecond(L1B_time_sec, L1B_time_msec, L1B_time_usec, L1B_time_nsec) is includedas the signaling in the preamble of the physical layer frame, thepreamble processing section 232 processes the time information of them.However, in this case, the L1 detailed information (FIG. 13 or 15) doesnot include time information.

Further, in the case where the L1D transmission method is adopted, sinceL1 detailed information (FIG. 17) including time information of a unitof second, a unit of millisecond, a unit of microsecond and a unit ofnanosecond (L1D_time_sec, L1D_time_msec, L1D_time_usec, L1D_time_nsec)is included as the signaling in the preamble of the physical layerframe, the preamble processing section 232 processes the timeinformation of them. However, in this case, the L1 basic information(FIG. 16) does not include time information.

The data processing section 233 performs a process relating to dataincluded in the payload (Payload) of the physical layer frame.

It is to be noted that, though not depicted in FIG. 21, in the waveformprocessing section 201, a processing section is provided which performsa process relating to a guard interval, a process relating to the PAPR,a process relating to FFT (Fast Fourier Transform), a process relatingto the MISO and a process relating to a symbol of a pilot, and theprocesses are performed.

(Reception Side Data Process)

Now, a flow of the reception data process executed by the receptionapparatus 20 of FIG. 18 is described with reference to a flow chart ofFIG. 22.

At step S201, the waveform processing section 201 performs a waveformprocess. In this waveform process, an OFDM signal transmitted from thetransmission apparatus 10 (FIG. 18) though the transmission line 30 isreceived, and a signal process for the OFDM signal is performed.Further, data and signaling are processed by the bootstrap processingsection 231, preamble processing section 232 and data processing section233.

Here, in the case where the L1B+L1D transmission method is adopted,since L1 basic information (FIG. 10) including time information of aunit of microsecond and a unit of nanosecond (L1B_time_usec,L1B_time_nsec) and L1 detailed information (FIG. 11) including timeinformation of a unit of second and a unit of millisecond (L1D_time_sec,L1D_time_msec) are included as the signaling in the preamble of thephysical layer frame, the preamble processing section 232 processes thetime information.

On the other hand, in the case where the L1B transmission method a orthe L1B transmission method b is adopted, since L1 basic information(FIG. 12 or 14) including time information of a unit of second, a unitof millisecond, a unit of microsecond and a unit of nanosecond(L1B_time_sec, L1B_time_msec, L1B_time_usec, L1B_time_nsec) is includedas the signaling in the preamble of the physical layer frame, thepreamble processing section 232 processes the time information.

Further, in the case where the L1D transmission method is adopted, sinceL1 detailed information (FIG. 17) of time information of a unit ofsecond, a unit of millisecond, a unit of microsecond and a unit ofnanosecond (L1D_time_sec, L1D_time_msec, L1D_time_usec, L1D_time_nsec)is included as the signaling in the preamble of the physical layerframe, the preamble processing section 232 processes the timeinformation.

At step S202, the frame deinterleave processing section 202 performs aframe deinterleave process. In this frame deinterleave process, suchprocesses as deinterleave in a frequency direction or a time directionare performed.

At step S203, the De-BICM processing section 203 performs a demodulationand decoding process. In this demodulation and decoding process, suchprocesses as orthogonal demodulation, bit deinterleave and an errorcorrection process are performed.

At step S204, the output format processing section 204 performs anoutput data process. In this output data process, a necessary process isperformed for inputted data, and resulting data is outputted as anoutput stream.

A flow of the reception side data process is described above. In thisreception side data process, by adopting the L1B+L1D transmissionmethod, L1B transmission method a, L1B transmission method b or L1Dtransmission method, signaling in which time information of a unit ofsecond, time information of a unit of millisecond, time information of aunit of microsecond and time information of a unit of nanosecond areincluded in information of at least one of the L1 basic information andthe L1 detailed information is acquired from the preamble of thephysical layer frame and is processed.

Then, since the time obtained from the time information has accuracyhigher than the accuracy of a unit of millisecond (accuracy of a unit ofmicrosecond or accuracy of a unit of nanosecond), in the case where theframe mode is the symbol-aligned mode, when the frame mode is thesymbol-aligned mode, the error (jitters) from the time indicated by thetime information can be suppressed even with a physical layer frame inwhich the frame length (frame time) is not units of integermilliseconds.

Therefore, errors of time arising from the accuracy of time informationtransmitted by signaling can be reduced. Furthermore, it is possible toprocess time information included in the signaling without consciousnessof whether or not the frame length of the physical layer frame (frametime) is units of integer milliseconds (for example, withoutconsciousness of a frame number of a physical layer frame or the like).

Further, if time information of a unit of microsecond of 10 bits andtime information of a unit of nanosecond of 10 bits are added to thesignaling, then accuracy of a level similar to that of the PTP can beimplemented. Alternatively, if only time information of a unit ofmicrosecond of 10 bits is added, then accuracy that is equal to orhigher than that of a system in the present circumstances and issufficient can be implemented. It is to be noted that, in the lattercase, since time information of a unit of microsecond of 10 bits istransmitted additionally, information for 10 bits is reduced incomparison with that in an alternative case in which both timeinformation of the former is transmitted additionally, and thetransmission efficiency can be improved.

Further, since sufficient accuracy of signaling can be implemented onlyby adding time information of a unit of microsecond or a unit ofnanosecond, as the transmission side data process, there is no necessityto perform a complicated process in comparison with existing processes(it is easy to treat data). Further, since the information to be addedto the signaling is time information itself, it does not have adependence relation with any other parameter included in the signaling,and, for example, even if expansion of standards is performed in thefuture, there is little possibility that the information may beinfluenced by the expansion of standards.

-   <5. Modifications>

While, in the foregoing description, ATSC (especially, ATSC3.0) that isa method adopted in the United States and so forth is described as astandard for digital broadcasting, the present technology may be appliedalso to ISDB (Integrated Services Digital Broadcasting) that is a methodadopted in Japan and so forth, DVB (Digital Video Broadcasting) that isa method adopted in European countries and so forth or the like.Further, while the foregoing description is given taking ATSC3.0 adoptedby the IP transmission method as an example, the present technology maybe applied not only to the IP transmission method but also to othermethods such as, for example, MPEG2-TS (Transport Stream) method.

Further, in regard to digital broadcasting, the present technology canbe applied not only to terrestrial broadcasting but also to satellitebroadcasting that utilizes a broadcasting satellite (BS: BroadcastingSatellite), a communication satellite (CS: Communication Satellite) orthe like, cable broadcasting such as cable television (CATV) or the likeand so forth.

Further, while, in the foregoing description, the time information isdescribed taking information of time prescribed by the PTP (Precise TimeProtocol) as an example, the time information is not limited to the PTP,but arbitrary information of time such as, for example, information oftime prescribed by the NTP (Network Time Protocol), information of timeprescribed by the 3GPP (Third Generation Partnership Project),information of time included in GPS (Global Positioning System)information or information of time of other forms determined uniquelycan be adopted.

Furthermore, the present technology can be applied also to predeterminedstandards (standards other than standards for digital broadcasting)prescribed on the assumption that, as the transmission line, atransmission line other than a broadcasting network, namely, acommunication line (communication network) such as the Internet or atelephone network or the like is utilized. In this case, as thetransmission line 30 of the transmission system 1 (FIG. 1), acommunication line such as the Internet or a telephone network isutilized, and the transmission apparatus 10 can be a server provided onthe Internet. Further, by configuring the reception apparatus 20 so asto have a communication function, the transmission apparatus 10 (server)performs a process in accordance with a request from the receptionapparatus 20. Further, the reception apparatus 20 processes datatransmitted thereto from the transmission apparatus 10 (sever) throughthe transmission line 30 (communication line).

Further, the designation such as signaling described hereinabove is anexample, and some other designation is sometimes used. However, thedifference in designation is a formal difference and is not different insubstantial contents of the signaling of the target.

-   <6. Configuration of Computer>

While the series of processes described hereinabove can be executed byhardware, it can otherwise be executed by software. In the case wherethe series of processes is executed by software, a program thatconstructs the software is installed into a computer. FIG. 23 is a viewdepicting an example of a hardware configuration of a computer thatexecutes the series of processes described hereinabove by a program.

In the computer 1000, a CPU (Central Processing Unit) 1001, a ROM (ReadOnly Memory) 1002 and a RAM (Random Access Memory) 1003 are connected toeach other by a bus 1004. To the bus 1004, an input/output interface1005 is connected further. To the input/output interface 1005, aninputting section 1006, an outputting section 1007, a recording section1008, a communication section 1009 and a drive 1010 are connected.

The inputting section 1006 is configured, for example, from a keyboard,a mouse, a microphone and so forth. The outputting section 1007 isconfigured, for example, from a display, a speaker and so forth. Therecording section 1008 includes a hard disk, a nonvolatile memory or thelike. The communication section 1009 includes, for example, a networkinterface. The drive 1010 drives a removable medium 1011 such as amagnetic disk, an optical disk, a magneto-optical disk or asemiconductor memory.

In the computer 1000 configured in such a manner as described above, theCPU 1001 loads a program recorded, for example, in the ROM 1002 or therecording section 1008 into the RAM 1003 through the input/outputinterface 1005 and the bus 1004 and executes the program to perform theseries of processes described hereinabove.

The program to be executed by the computer 1000 (CPU 1001) can berecorded into and provided, for example, as a removable medium 1011 as apackage medium. Further, the program can be provided through a wired orwireless transmission medium such as a local area network, the Internetor a digital satellite broadcast.

In the computer 1000, the program can be installed into the recordingsection 1008 through the input/output interface 1005 by loading aremovable medium 1011 into the drive 1010. Further, the program can bereceived through a wired or wireless transmission medium by thecommunication section 1009 and installed into the recording section1008. Alternatively, the program can be installed into the ROM 1002 orthe recording section 1008 in advance.

Here, in the present specification, the processes that are performed inaccordance with the program by the computer need not necessarily beperformed in a time series in accordance with the order described as aflow chart. In other words, the processes performed in accordance withthe program by the computer include also processes that are executed inparallel or individually (for example, parallel processes or processesby an object). Further, the program may be processed by one computer(processor) or may be processed in a distributed manner by a pluralityof computers.

It is to be noted that the embodiment of the present technology is notlimited the embodiment described hereinabove but can be altered invarious manners without departing from the subject matter of the presenttechnology.

Further, the present technology can take also the followingconfiguration.

-   (1)

A data processing apparatus, including:

a generation section configured to generate signaling including timeinformation having accuracy of time according to a frame length of aphysical layer frame; and

a processing section configured to process the signaling so as to beincluded into a preamble of the physical layer frame.

-   (2)

The data processing apparatus according to (1), in which

the signaling includes first information and second information that isread out after the first information, and

the time information is included in at least one of the firstinformation and the second information.

-   (3)

The data processing apparatus according to (2), in which

the frame length of the physical layer frame has accuracy higher than aunit of millisecond, and

the time information has accuracy higher than a unit of millisecond.

-   (4)

The data processing apparatus according to (3), in which

the second information includes time information of a unit of second andtime information of a unit of millisecond, and

the first information includes at least one of time information of aunit of microsecond, and time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (5)

The data processing apparatus according to (3), in which

the first information includes time information of a unit of second,time information of a unit of millisecond, and time information of aunit of microsecond or time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (6)

The data processing apparatus according to (3), in which

the second information includes time information of a unit of second,time information of a unit of millisecond, and time information of aunit of microsecond or time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (7)

The data processing apparatus according to (2), in which

the frame length of the physical layer frame has accuracy of a unit ofmillisecond, and

the time information has accuracy higher than a unit of millisecond.

-   (8)

The data processing apparatus according to any one of (2) to (7), inwhich

the physical layer frame is a physical layer frame prescribed by ATSC(Advanced Television Systems Committee) 3.0,

the first information is L1 basic information (L1-Basic) included in thepreamble prescribed by ATSC3.0, and

the second information is L1 detailed information (L1-Detail) includedin the preamble prescribed by ATSC3.0.

-   (9)

The data processing apparatus according to any one of (3) to (8), inwhich

a first mode in which the frame length of the physical layer frame isadjusted to units of millisecond and a second mode in which the framelength of the physical layer frame is not adjusted, and

in the case where the second mode is set, the time information hasaccuracy higher than a unit of millisecond.

-   (10)

A data processing method of a data processing apparatus, including thesteps by the data processing apparatus of:

generating signaling including time information having accuracy of timeaccording to a frame length of a physical layer frame; and

processing the signaling so as to be included into a preamble of thephysical layer frame.

-   (11)

A data processing apparatus, including:

a processing section configured to process signaling included in apreamble of a physical layer frame and including time information havingaccuracy of time according to a frame length of the physical layerframe.

-   (12)

The data processing apparatus according to (11), in which

the signaling includes first information and second information that isread out after the first information, and

the time information is included in at least one of the firstinformation and the second information.

-   (13)

The data processing apparatus according to (12), in which

the frame length of the physical layer frame has accuracy higher than aunit of millisecond, and

the time information has accuracy higher than a unit of millisecond.

-   (14)

The data processing apparatus according to (13), in which

the second information includes time information of a unit of second andtime information of a unit of millisecond, and

the first information includes at least one of time information of aunit of microsecond, and time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (15)

The data processing apparatus according to (13), in which

the first information includes time information of a unit of second,time information of a unit of millisecond, and time information of aunit of microsecond or time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (16)

The data processing apparatus according to (13), in which

the second information includes time information of a unit of second,time information of a unit of millisecond, and time information of aunit of microsecond or time information of a unit of microsecond andtime information of a unit of nanosecond.

-   (17)

The data processing apparatus according to (12), in which

the frame length of the physical layer frame has accuracy of a unit ofmillisecond, and

the time information has accuracy higher than a unit of millisecond.

-   (18)

The data processing apparatus according to any one of (12) to (17), inwhich

the physical layer frame is a physical layer frame prescribed by ATSC(Advanced Television Systems Committee) 3.0,

the first information is L1 basic information (L1-Basic) included in thepreamble prescribed by ATSC3.0, and

the second information is L1 detailed information (L1-Detail) includedin the preamble prescribed by ATSC3.0.

-   (19)

The data processing apparatus according to any one of (13) to (18), inwhich

a first mode in which the frame length of the physical layer frame isadjusted to units of millisecond and a second mode in which the framelength of the physical layer frame is not adjusted, and

in the case where the second mode is set, the time information hasaccuracy higher than a unit of millisecond.

-   (20)

A data processing method of a data processing apparatus, including thestep by the data processing apparatus of:

processing signaling included in a preamble of a physical layer frameand including time information having accuracy of time according to aframe length of the physical layer frame.

REFERENCE SIGNS LIST

1 Transmission system, 10 Transmission apparatus, 20 Receptionapparatus, 30 Transmission line, 101 Input format processing section,102 BICM processing section, 103 Frame interleave processing section,104 Waveform processing section, 131 Data processing section, 132Preamble processing section, 133 Bootstrap processing section, 201Waveform processing section, 202 Frame deinterleave processing section,203 De-BICM processing section, 204 Output format processing section,231 Bootstrap processing section, 232 Preamble processing section, 233Data processing section, 1000 Computer, 1001 CPU

1. (canceled)
 2. A reception apparatus, comprising: receive circuitryconfigured to receive a broadcast signal having a physical layer frameincluding a preamble, the preamble including signaling data, thesignaling data including a time information flag, the time informationflag indicating the presence or absence of time information in thesignaling data, and, if the time information is present in the signalingdata, the time information flag indicating which of two or more fieldsof different units of time are present in the time information in thesignaling data; and processing circuitry configured to process thereceived broadcast signal.
 3. The reception apparatus according to claim2, wherein a first value of the time information flag indicates thattime information is not present in the signaling data.
 4. The receptionapparatus according to claim 2, wherein a second value of the timeinformation flag indicates that the time information is present in thesignaling data and includes a first field in units of seconds, and asecond field in units of milliseconds.
 5. The reception apparatusaccording to claim 2, wherein a third value of the time information flagindicates that the time information is present in the signaling data andincludes a first field in units of seconds, a second field in units ofmilliseconds, and a third field in units of microseconds.
 6. Thereception apparatus according to claim 2, wherein a fourth value of thetime information flag indicates that the time information is present inthe signaling data and includes a first field in units of seconds, asecond field in units of milliseconds, a third field in units ofmicroseconds, and a fourth field in units of nanoseconds.
 7. Thereception apparatus according to claim 2, wherein: the signaling dataincludes first information and second information, the secondinformation being arranged in the preamble after the first information,the time information flag is included in the first information, and thetime information, if present, is included in the second information. 8.The reception apparatus according to claim 7, wherein: the physicallayer frame is a physical layer frame consistent with AdvancedTelevision Systems Committee (ATSC) 3.0, the first information is L1basic information (L1-Basic) included in a preamble consistent withATSC3.0, and the second information is L1 detailed information(L1-Detail) included in the preamble consistent with ATSC3.0.
 9. Thereception apparatus according to claim 2, wherein the time informationindicates a time of the start of the physical layer frame.
 10. Thereception apparatus according to claim 2 comprising: a display, whereinthe processing circuitry is configured to control the display inaccordance with the processed received broadcast signal.
 11. A method ofa reception apparatus, comprising: receiving a broadcast signal having aphysical layer frame including a preamble, the preamble includingsignaling data, the signaling data including a time information flag,the time information flag indicating the presence or absence of timeinformation in the signaling data, and, if the time information ispresent in the signaling data, the time information flag indicatingwhich of two or more fields of different units of time are present inthe time information in the signaling data; and processing the receivedbroadcast signal.
 12. The method according to claim 11, wherein a firstvalue of the time information flag indicates that time information isnot present in the signaling data.
 13. The method according to claim 11,wherein a second value of the time information flag indicates that thetime information is present in the signaling data and includes a firstfield in units of seconds, and a second field in units of milliseconds.14. The method according to claim 11, wherein a third value of the timeinformation flag indicates that the time information is present in thesignaling data and includes a first field in units of seconds, a secondfield in units of milliseconds, and a third field in units ofmicroseconds.
 15. The method according to claim 11, wherein a fourthvalue of the time information flag indicates that the time informationis present in the signaling data and includes a first field in units ofseconds, a second field in units of milliseconds, a third field in unitsof microseconds, and a fourth field in units of nanoseconds.
 16. Themethod according to claim 11, wherein: the signaling data includes firstinformation and second information, the second information beingarranged in the preamble after the first information, the timeinformation flag is included in the first information, and the timeinformation, if present, is included in the second information.
 17. Themethod according to claim 16, wherein: the physical layer frame is aphysical layer frame consistent with Advanced Television SystemsCommittee (ATSC) 3.0, the first information is L1 basic information(L1-Basic) included in a preamble consistent with ATSC3.0, and thesecond information is L1 detailed information (L1-Detail) included inthe preamble consistent with ATSC3.0.
 18. The method according to claim11, wherein the time information indicates a time of the start of thephysical layer frame.
 19. The method according to claim 11, wherein: thereception apparatus includes a display, and the method comprisescontrolling the display in accordance with the processed receivedbroadcast signal.